To make it simple, I want to keep my stock single cd. I already have a subwoofer I installed. So can anyone give me the easiest set up with what to replace all 4 speakers with (doesn't have to have high watts) and a simple 4 channel amp that takes high input from the radio (no RCAs). Is there a 5 channel with a dedicated subwoofer channel. All in all, looking for a simple project. The reason I don't want to change the HU, most of mine have been rippoed off by some junkie or something. Thx